Modified succinimides (VIII)

ABSTRACT

Disclosed are polyaminoalkenyl or alkyl succinimides which have been modified by treatment with a compound of the formula: ##STR1## R 4  is an alkylene group of from 2 to 3 carbon atoms or an alkylene group of from 2 to 3 carbon atoms substituted with from 1 to 3 alkyl groups of from 1 to 2 carbon atoms each. The modified polyamino alkenyl or alkyl succinimides of this invention have been found to possess dispersancy and detergency in lubricating oils. These modified succinimides are also useful as dispersants and detergents in fuels.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to additives which are useful as dispersantsand/or detergents in lubricating oils. In particular, this invention isdirected toward polyamino alkenyl or alkyl succinimides which have beenmodified by treatment with a thiocarbonate of the formula: ##STR2##wherein R₄ is an alkylene group of from 2 to 3 carbon atoms or analkylene group of from 2 to 3 carbon atoms substituted with from 1 to 3alkyl groups of from 1 to 2 carbon atoms each. The modified polyaminoalkenyl or alkyl succinimides of this invention have been found topossess dispersancy and/or detergency in lubricating oils. Thesemodified succinimides are also useful as dispersants and/or detergentsin fuels.

2. Prior Art

Alkenyl or alkyl succinimides have been previously modified withalkylene oxides to produce poly(oxyalkylene)hydroxy derivatives thereof.These alkylene oxide treated succinimides are taught as additives forlubricating oils (see U.S. Pat. Nos. 3,373,111 and 3,367,943). Karol etal, U.S. Pat. No. 4,482,464, disclose succinimides which have beenmodified by treatment with a hydroxyalkylene carboxylic acid selectedfrom glycolic acid, lactic acid, 2-hydroxymethyl propionic acid and2,2'-bis-hydroxymethylpropionic acid. These modified succinimides ofKarol et al are disclosed as lubricating oil additives. Anderson, U.S.Pat. No. 3,301,784 discloses mono- andbis-(N-hydrocarbyl(alkylsubstituted)-2-pyrolidinones as dispersantadditives for lubricating oils. Heiba, U.S. Pat. No. 4,182,715 disclosesthe reaction of gamma-alkyl-gamma butyrolactones having an alkylsubstituent of at least 16 carbon atoms in length with amines orpolyalkylenepolyamines. The products of this reaction are disclosed asmultifunctional agents in lubricants, fuels, coolants and other organicfluids. Babic, U.S. Pat. No. 4,439,612 discloses the reaction of carbondisulfide with hydrocarbyl succinimides to form thioureas. The thioureasdisclosed therein are useful in gasoline and diesel engine dispersancy,oxidation stability and friction modification. However, there is noteaching in these patents or apparently elsewhere of the modifiedalkenyl or alkyl succinimides of this invention.

SUMMARY OF THE INVENTION

It has now been found that polyamino alkenyl or alkyl succinimides maybe modified by reaction with a thiocarbonate of Formula I: ##STR3##wherein R₄ is an alkylene group of from 2 to 3 carbon atoms or analkylene group of from 2 to 3 carbon atoms substituted with from 1 to 3alkyl groups of from 1 to 2 carbon atoms each.

As noted above, the modified polyamino alkenyl or alkyl succinimides ofthis invention possess dispersancy and/or detergency properties whenused in either lubricating oils or fuels. Thus, another aspect of thisinvention is a lubricating oil composition comprising a major amount ofan oil of lubricating viscosity and an amount of a modified polyaminoalkyl or alkenyl succinimide of this invention sufficient to providedispersancy and/or detergency.

Another aspect of this invention is a fuel composition comprising amajor amount of a hydrocarbon boiling in a gasoline or diesel range andan amount of a modified polyamino alkyl or alkenyl succinimide of thisinvention sufficient to provide dispersancy and/or detergency.

In general, the alkenyl or alkyl group of the succinimide is from 10 to300 carbon atoms. While the modified succinimides of this inventionpossess good detergency properties even for alkenyl or alkyl groups ofless than 20 carbon atoms, dispersancy is enhanced when the alkenyl oralkyl group is at least 20 carbon atoms. Accordingly, in a preferredembodiment, the alkenyl or alkyl group of the succinimide is at least 20carbon atoms.

DETAILED DESCRIPTION OF THE INVENTION

The modified polyamino alkenyl or alkyl succinimides of this inventionare prepared by contacting a polyamino alkenyl or alkyl succinimide witha compound of Formula I at a temperature sufficient to cause reaction.

In particular, the reaction is conducted by contacting the compound ofFormula I with the polyamino alkenyl or alkyl succinimide at atemperature sufficient to cause reaction. Reaction temperatures of from0° C. to about 250° C. are preferred with temperatures of from about100° C. to 200° C. being most preferred.

The reaction may be conducted neat--that is, both the alkenyl or alkylsuccinimide and the compound of Formula I are combined in the properratio, either alone or in the presence of a catalyst, such as an acidic,basic or Lewis acid catalyst, and then stirred at the reactiontemperature. Examples of suitable catalysts include, for instance, borontrifluoride, alkyl or aryl sulfonic acid, alkali or alkaline carbonate.

Alternatively, the reaction may be conducted in a diluent. For example,the reactants may be combined in a solvent such as toluene, xylene, oilor the like, and then stirred at the reaction temperature. Afterreaction completion, volatile components may be stripped off. when adiluent is employed, it is preferably inert to the reactants andproducts formed and is generally used in an amount sufficient to insureefficient stirring.

Water, which can be present in the polyamino alkenyl or alkylsuccinimide, may be removed from the reaction system either before orduring the course of the reaction via azeotroping or distillation. Afterreaction completion, the system can be stripped at elevated temperatures(100° C. to 250° C.) and reduced pressures to remove any volatilecomponents which may be present in the product.

Another embodiment of the above process is a continuous flow system inwhich the alkenyl or alkyl succinic anhydride and polyamine are added atthe front end of the flow while the compound of Formula I is addedfurther downstream in the system.

Mole ratios of the compound of Formula I to the basic amine nitrogen ofthe polyamino alkenyl or alkyl succinimide employed in this inventionare generally in the range of from about 0.2 to 1 to about 5:1, althoughpreferably from about 0.5:1 to about 2:1.

The reaction is generally complete from within 0.5 to 10 hours.

As used herein, the term "molar charge of compound of Formula I to thebasic nitrogen of an alkenyl or alkyl succinimide" means that the molarcharge of a compound of Formula I employed in the reaction is based uponthe theoretical number of basic nitrogens contained in the succinimide.Thus, when 1 equivalent of triethylene tetraamine (TETA) is reacted withan equivalent of succinic anhydride, the resulting monosuccinimide willtheoretically contain 3 basic nitrogens. Accordingly, a molar charge of1 would require that a mole of a compound of Formula I be added for eachbasic nitrogen or in this case 3 moles of a compound of Formula I foreach mole of monosuccinimide prepared from TETA.

A. ALKENYL OR ALKYL SUCCINIMIDES

The modified polyamino alkenyl or alkyl succinimides of this inventionare prepared from a polyamino alkenyl or alkyl succinimide. In turn,these materials are prepared by reacting an alkenyl or alkyl succinicanhydride with a polyamine group as shown in reaction (2) below:##STR4## wherein R is an alkenyl or alkyl group of from 10 to 300 carbonatoms; and R¹ is the remainder of the polyamino moiety.

These polyamino alkenyl or alkyl succinimides that can be used hereinare disclosed in numerous references and are well known in the art.Certain fundamental types of succinimides and related materialsencompassed by the term of art "succinimide" are taught in U.S. Pat.Nos. 2,992,708; 3,018,291; 3,024,237; 3,100,673; 3,219,666; 3,172,892;and 3,272,746, the disclosures of which are hereby incorporated byreference. The term "succinimide" is understood in the art to includemany of the amide, imide and amidine species which are also formed bythis reaction. The predominant product however is succinimide and thisterm has been generally accepted as meaning the product of a reaction ofan alkenyl substituted succinic acid or anhydride with a polyamine asshown in reaction (1) above. As used herein, included within this termare the alkenyl or alkyl mono-, bis-succinimides and other higheranalogs.

A(1) Succinic Anhydride

The preparation of the alkenyl-substituted succinic anhydride byreaction with a polyolefin and maleic anhydride has been described,e.g., U.S. Pat. Nos. 3,018,250 and 3,024,195. Such methods include thethermal reaction of the polyolefin with maleic anhydride and thereaction of a halogenated polyolefin, such as a chlorinated polyolefin,with maleic anhydride. Reduction of the alkenyl-substituted succinicanhydride yields the corresponding alkyl derivative. Alternatively, thealkenyl substituted succinic anhydride may be prepared as described inU.S. Pat. Nos. 4,388,471 and 4,450,281 which are totally incorporatedherein by reference.

Polyolefin polymers for reaction with the maleic anhydride are polymerscomprising a major amount of C₂ to C₅ mono-olefin, e.g., ethylene,propylene, butylene, isobutylene and pentene. The polymers can behomopolymers such as polyisobutylene as well as copolymers of 2 or moresuch olefins such as copolymers of: ethylene and propylene, butylene,and isobutylene, etc. Other copolymers include those in which a minoramount of the copolymer monomers, e.g., 1 to 20 mole percent is a C₄ toC₈ nonconjugated diolefin, e.g., a copolymer of isobutylene andbutadiene or a copolymer of ethylene, propylene and 1,4-hexadiene, etc.

The polyolefin polymer, represented in FIG. II as R, usually containsfrom about 10 to 300 carbon atoms, although preferably 10 to 200 carbonatoms, more preferably 12 to 100 carbon atoms and most preferably 20 to100 carbon atoms.

A particularly preferred class of olefin polymers comprises thepolybutenes, which are prepared by polymerization of one or more of1-butene, 2-butene and isobutene. Especially desirable are polybutenescontaining a substantial proportion of units derived from isobutene. Thepolybutene may contain minor amounts of butadiene which may or may notbe incorporated in the polymer. Most often the isobutene unitsconstitute 80%, preferably at least 90%, of the units in the polymer.These polybutenes are readily available commercial materials well knownto those skilled in the art. Disclosures thereof will be found, forexample, in U.S. Pat. Nos. 3,215,707; 3,231,587; 3,515,669; and3,579,450, as well as U.S. Pat. No. 3,912,764. The above areincorporated by reference for their disclosures of suitable polybutenes.

In addition to the reaction of a polyolefin with maleic anhydride, manyother alkylating hydrocarbons may likewise be used with maleic anhydrideto produce alkenyl succinic anhydride. Other suitable alkylatinghydrocarbons include cyclic, linear, branched and internal or alphaolefins with molecular weights in the range 100-4,500 or more withmolecular weights in the range of 200-2,000 being more preferred. Forexample, alpha olefins obtained from the thermal cracking of paraffinwax. Generally, these olefins range from 5-20 carbon atoms in length.Another source of alpha olefins is the ethylene growth process whichgives even number carbon olefins. Another source of olefins is by thedimerization of alpha olefins over an appropriate catalyst such as thewell known Ziegler catalyst. Internal olefins are easily obtained by theisomerization of alpha olefins over a suitable catalyst such as silica.

A(2) Polyamine

The polyamine employed to prepare the polyamino alkenyl or alkylsuccinimides is preferably a polyamine having from 2 to about 12 aminenitrogen atoms and from 2 to about 40 carbon atoms. The polyamine isreacted with an alkenyl or alkyl succinic anhydride to produce thepolyamino alkenyl or alkyl succinimide, employed in this invention. Thepolyamine is so selected so as to provide at least one basic amine persuccinimide. Since the reaction of an amino nitrogen of a polyaminoalkenyl or alkyl succinimide with a compound of Formula I is believed toproceed through a secondary or primary amine, at least one of the basicamine atoms of the alkenyl or alkyl succinimide must either be a primaryamine or a secondary amine. Accordingly, in those instances in which thesuccinimide contains only one basic amine, that amine must either be aprimary amine or a secondary amine. The polyamine preferably has acarbon-to-nitrogen ratio of from about 1:1 to about 10:1.

The polyamine portion of the polyamino alkenyl or alkyl succinimide maybe substituted with substituents selected from (A) hydrogen, (B)hydrocarbyl groups of from 1 to about 10 carbon atoms, (C) acyl groupsof from 2 to about 10 carbon atoms, and (D) monoketo, monohydroxy,mononitro, monocyano, lower alkyl and lower alkoxy derivatives of (B)and (C). "Lower", as used in terms like lower alkyl or lower alkoxy,means a group containing from 1 to about 6 carbon atoms. At least one ofthe substituents on one of the amines of the polyamine is hydrogen,e.g., at least one of the basic nitrogen atoms of the polyamine is aprimary or secondary amino nitrogen atom.

Hydrocarbyl, as used in describing the polyamine components of thisinvention, denotes an organic radical composed of carbon and hydrogenwhich may be aliphatic, alicyclic, aromatic or combinations thereof,e.g., aralkyl. Preferably, the hydrocarbyl group will be relatively freeof aliphatic unsaturation, i.e., ethylenic and acetylenic, particularlyacetylenic unsaturation. The substituted polyamines of the presentinvention are generally, but not necessarily, N-substituted polyamines.Exemplary hydrocarbyl groups and substituted hydrocarbyl groups includealkyls such as methyl, ethyl, propyl, butyl, isobutyl, pentyl, hexyl,octyl, etc., alkenyls such as propenyl, isobutenyl, hexenyl, octenyl,etc., hydroxyalkyls, such as 2-hydroxyethyl, 3-hydroxypropyl,hydroxyisopropyl, 4-hydroxybutyl, etc., ketoalkyls, such as2-ketopropyl, 6-ketooctyl, etc., alkoxy and lower alkenoxy alkyls, suchas ethoxyethyl, ethoxypropyl, propoxyethyl, propoxypropyl,2-(2-ethoxyethoxy)ethyl, 2-(2-(2-ethoxy-ethoxy)ethoxy)ethyl,3,6,9,12-tetraoxatetradecyl, 2-(2-ethoxyethoxy)hexyl, etc. The acylgroups of the aforementioned (C) substituents are such as propionyl,acetyl, etc. The more preferred substituents are hydrogen, C₁ -C₆ alkylsand C₁ -C₆ hydroxyalkyls.

In a substituted polyamine the substituents are found at any atomcapable of receiving them. The substituted atoms, e.g., substitutednitrogen atoms, are generally geometrically inequivalent, andconsequently the substituted amines finding use in the present inventioncan be mixtures of mono- and polysubstituted polyamines with substituentgroups situated at equivalent and/or inequivalent atoms.

The more preferred polyamine finding use within the scope of the presentinvention is a polyalkylene polyamine, including alkylene diamine, andincluding substituted polyamines, e.g., alkyl substituted polyalkylenepolyamine. Preferably, the alkylene group contains from 2 to 6 carbonatoms, there being preferably from 2 to 3 carbon atoms between thenitrogen atoms. Such groups are exemplified by ethylene, 1,2-propylene,2,2-dimethyl-propylene, trimethylene, etc. Examples of such polyaminesinclude ethylene diamine, diethylene triamine, di(trimethylene)triamine,dipropylene triamine, triethylene tetramine, tripropylene tetramine,tetraethylene pentamine, and pentaethylene hexamine. Such aminesencompass isomers such as branched-chain polyamines and the previouslymentioned substituted polyamines, including hydrocarbyl-substitutedpolyamines. Among the polyalkylene polyamines, those containing 2-12amine nitrogen atoms and 2-24 carbon atoms are especially preferred, andthe C₂ -C₅ alkylene polyamines are most preferred, in particular, thelower polyalkylene polyamines, e.g., ethylene diamine, dipropylenetriamine, etc.

The polyamine component also may contain hetero-cyclic polyamines,heterocyclic substituted amines and substituted heterocyclic compounds,wherein the hetero-cycle comprises one or more 5-6 membered ringscontaining oxygen and/or nitrogen. Such heterocycles may be saturated orunsaturated and substituted with groups selected from the aforementioned(A), (B), (C) and (D). The heterocycles are exemplified by piperazines,such as 2-methylpiperazine, N-(2-hydroxyethyl)piperazine,1,2-bis-(N-piperazinyl)ethane, and N,N'-bis(N-piperazinyl)piperazine,2-methylimidazoline, 3-aminopiperidine, 2-aminopyridine,2-(3-aminoethyl)-3-pyrroline, 3-aminopyrrolidine,N-(3-aminopropyl)-morpholine, etc. Among the heterocyclic compounds, thepiperazines are preferred.

Typical polyamines that can be used to form the compounds of thisinvention include the following: ethylene diamine, 1,2-propylenediamine, 1,3-propylene diamine, diethylene triamine, triethylenetetramine, hexamethylene diamine, tetraethylene pentamine,methylaminopropylene diamine, N-(betaaminoethyl)piperazine,N,N'-di(betaaminoethyl)piperazine,N,N'-di(beta-aminoethyl)imidazolidone-2,N-(beta-cyanoethyl)ethane-1,2-diamine, 1,3,6,9-tetraaminooctadecane,1,3,6-triamino-9-oxadecane, N-(beta-aminoethyl)diethanolamine,N-methyl-1,2-propanediamine,2-(2-aminoethylamino)-ethanol,2-[2-(2-aminoethylamino)ethylamino]-ethanol.

Another group of suitable polyamines are the propyleneamines,(bisaminopropylethylenediamines). Propyleneamines are prepared by thereaction of acrylonitrile with an ethyleneamine, for example, anethyleneamine having the formula H₂ N(CH₂ CH₂ NH)_(Z) H wherein Z is aninteger from 1 to 5, followed by hydrogenation of the resultantintermediate. Thus, the product prepared from ethylene diamine andacrylonitrile would be H₂ N(CH₂)₃ NH(CH₂)₂ NH(CH₂)₃ NH₂.

In many instances the polyamine used as a reactant in the production ofsuccinimides of the present invention is not a single compound but amixture in which one or several compounds predominate with the averagecomposition indicated. For example, tetraethylene pentamine prepared bythe polymerization of aziridine or the reaction of dichloroethylene andammonia will have both lower and higher amine members, e.g., triethylenetetramine, substituted piperazines and pentaethylene hexamine, but thecomposition will be largely tetraethylene pentamine and the empiricalformula of the total amine composition will closely approximate that oftetraethylene pentamine. Finally, in preparing the succinimide for usein this invention, where the various nitrogen atoms of the polyamine arenot geometrically equivalent, several substitutional isomers arepossible and are encompassed within the final product. Methods ofpreparation of polyamines and their reactions are detailed inSidgewick's "The Organic Chemistry of Nitrogen," Clarendon Press,Oxford, 1966; Noller's "Chemistry of Organic Compounds," Saunders,Philadelphia, 2nd Ed., 1957; and Kirk-Othmer's "Encyclopedia of ChemicalTechnology," 2nd Ed., especially Volumes 2, pp. 99-116.

The reaction of a polyamine with an alkenyl or alkyl succinic anhydrideto produce the polyamino alkenyl or alkyl succinimides is well known inthe art and is disclosed in U.S. Pat. Nos. 2,992,708; 3,018,291;3,024,237; 3,100,673; 3,219,666; 3,172,892 and 3,272,746. The above areincorporated herein by reference for their disclosures of preparingalkenyl or alkyl succinimides.

As noted above, the term "polyamino alkenyl or alkyl succinimide" refersto both polyamino alkenyl or alkyl mono- and bis-succinimides and to thehigher analogs of alkenyl or alkyl poly succinimides. Preparation of thebis- and higher analogs may be accomplished by controlling the molarratio of the reagents. For example, a product comprising predominantlymono- or bis-succinimide can be prepared by controlling the molar ratiosof the polyamine and succinic anhydride. Thus, if one mole of polyamineis reacted with one mole of an alkenyl or alkyl substituted succinicanhydride, a predominantly mono-succinimide product will be prepared. Iftwo moles of an alkenyl or alkyl substituted succinic anhydride arereacted per mole of polyamine, a bis-succinimide is prepared. Higheranalogs may likewise be prepared.

A particularly preferred class of polyamino alkenyl or alkylsuccinimides employed in the process of the instant invention may berepresented by Formula III ##STR5## wherein R is alkenyl or alkyl offrom 10 to 300 carbon atoms; R₂ is alkylene of 2 to 10 carbon atoms; R₃is hydrogen, lower alkyl or lower hydroxyl alkyl; a is an integer from 0to 10; and Z is --NH₂ or represents a group of Formula IV: ##STR6##wherein R is alkenyl or alkyl of from 10 to 300 carbon atoms; with theproviso that when Z is the group of Formula IV above, then a is not zeroand at least one of R₃ is hydrogen.

As indicated above, the polyamine employed in preparing the succinimideis often a mixture of different compounds having an average compositionindicated as the Formula III. Accordingly, in Formula III each value ofR₂ and R₃ may be the same as or different from other R₂ and R₃.

Preferably R is alkenyl or alkyl is preferably 10 to 200 carbon atomsand most preferably 20 to 100 carbon atoms.

Preferably R₂ is alkylene of 2 to 6 carbon atoms and most preferably iseither ethylene or propylene.

Preferably, R₃ is hydrogen.

Preferably, a is an integer from 1 to 6.

In formula III, the polyamino alkenyl or alkyl succinimides may beconveniently viewed as being composed of three moieties that is thealkenyl or alkyl moiety R, the succinimide moiety represented by theformula: ##STR7## and the polyamino moiety represented by the group##STR8##

The alkylene polyamines employed in this reaction are generallyrepresented by the formula:

    H.sub.2 N--R.sub.2 NH).sub.a --R.sub.2 NH.sub.2

wherein R₂ is an alkylene moiety of 2 to 10 carbon atoms and a is aninteger from about 0 to 10. However, the preparation of these alkylenepolyamines do not produce a single compound and cyclic heterocycles,such as piperazine, may be included to some extent in the alkylenediamines.

B. Compounds of Formula I

The thiocarbonates, I, of this invention react with a basic primary orsecondary amine of the polyamino moiety, V, to form thiocarbamates VI,and amines, VII, as shown in reaction (2) below: ##STR9## wherein R₄ isas defined above and R₆ and R₇ represent a polyamino moiety

If additional thiocarbonate, I, is added to the reaction, it will reactwith any available primary or secondary amine. Afterward, additionalthiocarbonate will react with the hydroxy group of either VI or VII toform polymers. This reaction may proceed to form this carbamate oreliminate CSO and form polyoxyalkylene compounds. Preferably, a molarcharge of from 0.2:1 to 5:1 of carbamate, XVI, to the basic nitrogen ofthe polyamino moiety of the alkenyl or alkyl succinimide is employed;more preferably 0.5:1 to 2:1.

Accordingly, another aspect of this invention is a product produced bythe process which comprises contacting a polyamino alkenyl or alkylsuccinimide with a compound of Formula I at a temperature sufficient tocause reaction.

The following are examples of suitable cyclic carbonates for use in thisinvention: 1,3-dioxolan-2-thione(ethylenethiocarbonate);4-methyl-1,3-dioxolan-2-thione(propylenethiocarbonate) and the like.

Cyclic thiocarbonates of Formula I may be readily prepared by knownreactions. For example, reaction of thiophosgene with a suitable alphaalkane diol or an alkan-1,3-diol yields a thiocarbonate for use withinthe scope of this invention (see U.S. Pat. No. 4,115,206 which isincorporated herein by reference).

Likewise, the cyclic carbonates useful for this invention may beprepared by transesterifiction of a suitable alpha alkane diol or analkan-1,3-diol with, e.g., diethyl thiocarbonate undertransesterification conditions. (See, for instance, U.S. Pat. Nos.4,384,115 and 4,423,205).

Lastly, thiocarbonates of Formula I may be prepared as in Synthesis Vol.4, 286 (1978) and Journal of Organic Chemistry, 34, 3011 (1969).

As used herein, the term "alpha alkane diol" means an alkane grouphaving two hydroxyl substituents wherein the hydroxyl substituents areon adjacent carbons to each other. Examples of alpha alkane diolsinclude 1,2-propanediol, 2,3-butanediol and the like.

The term "alkan-1,3-diol" means an alkane group having two hydroxylsubstituents wherein the hydroxyl substituents are beta substituted.That is, there is a methylene or a substituted methylene moiety betweenthe hydroxyl substituted carbons. Examples of alkan-1,3-diols includepropan-1,3-diol, pentan-2,4-diol and the like.

The alpha alkane diols, used to prepare the 1,3-dixolan-2-thionesemployed in this invention, are either commercially available or may beprepared from the corresponding olefin by methods known in the art. Forexample, the olefin may first react with a peracid, such as peroxyaceticacid or hydrogen peroxide to form the corresponding epoxide which isreadily hydrolyzed under acid or base catalysis to the alpha alkanediol. In another process, the olefin is first halogenated to a dihaloderivative and subsequently hydrolyzed to an alpha alkane diol byreaction first with sodium acetate and then with sodium hydroxide. Theolefins so employed are known in the art.

The alkan-1,3-diols, used to prepare the 1,3-dioxolan-2-thiones employedin this invention, are either commercially available or may be preparedby standard techniques, e.g., derivatizing malonic acid.

The modified polyamino succinimide of this invention can also be reactedwith boric acid or a similar boron compound to form borated dispersantshaving utility within the scope of this invention. In addition to boricacid (boron acid), examples of suitable boron compounds include boronoxides, boron halides and esters of boric acid. Generally from about 0.1equivalents to 10 equivalents of boron compound to the modifiedsuccinimide may be employed.

The modified polyamino alkenyl or alkyl succinimides of this inventionare useful as detergent and dispersant additives when employed inlubricating oils. When employed in this manner, the modified polyaminoalkenyl or alkyl succinimide additive is usually present in from 0.2 to10 percent by weight to the total composition and preferably at about0.5 to 5 percent by weight. The lubricating oil used with the additivecompositions of this invention may be mineral oil or synthetic oils oflubricating viscosity and preferably suitable for use in the crankcaseof an internal combustion engine. Crankcase lubricating oils ordinarilyhave a viscosity of about 1300 CSt 0° F. to 22.7 CSt at 210° F. (99°C.). The lubricating oils may be derived from synthetic or naturalsources. Mineral oil for use as the base oil in this invention includesparaffinic, naphthenic and other oils that are ordinarily used inlubricating oil compositions. Synthetic oils include both hydrocarbonsynthetic oils and synthetic esters. Useful synthetic hydrocarbon oilsinclude liquid polymers of alpha olefins having the proper viscosity.Especially useful are the hydrogenated liquid oligomers of C₆ to C₁₂alpha olefins such as 1-decene trimer. Likewise, alkyl benzenes ofproper viscosity such as didodecyl benzene, can be used. Usefulsynthetic esters include the esters of both monocarboxylic acid andpolycarboxylic acids as well as monohydroxy alkanols and polyols.Typical examples are didodecyl adipate, pentaerythritol tetracaproate,di-2-ethylhexyl adipate, dilaurylsebacate and the like. Complex estersprepared from mixtures of mono and dicarboxylic acid and mono anddihydroxy alkanols can also be used.

Blends of hydrocarbon oils with synthetic oils are also useful. Forexample, blends of 10 to 25 weight percent hydrogenated 1-decene trimerwith 75 to 90 weight percent 150 SUS (100° F.) mineral oil gives anexcellent lubricating oil base.

Additive concentrates are also included within the scope of theinvention. The concentrates of this invention usually include from about90 to 10 weight percent of an oil of lubricating viscosity and fromabout 10 to 90 weight percent of the complex additive of this invention.Typically, the concentrates contain sufficient diluent to make them easyto handle during shipping and storage. Suitable diluents for theconcentrates include any inert diluent, preferably an oil of lubricatingviscosity, so that the concentrate may be readily mixed with lubricatingoils to prepare lubricating oil compositions. Suitable lubricating oilswhich can be used as diluents typically have viscosities in the rangefrom about 35 to about 500 Saybolt Universal Seconds (SUS) at 100° F.(38° C.), although an oil of lubricating viscosity may be used.

Other additives which may be present in the formulation include rustinhibitors, foam inhibitors, corrosion inhibitors, metal deactivators,pour point depressants, antioxidants, and a variety of other well-knownadditives.

It is also contemplated the modified succinimides of this invention maybe employed as dispersants and detergents in hydraulic fluids, marinecrankcase lubricants and the like. When so employed, the modifiedsuccinimide is added at from about 0.1 to 10 percent by weight to theoil. Preferably, at from 0.5 to 5 weight percent.

When used in fuels, the proper concentration of the additive necessaryin order to achieve the desired detergency is dependent upon a varietyof factors including the type of fuel used, the presence of otherdetergents or dispersants or other additives, etc. Generally, however,and in the preferred embodiment, the range of concentration of theadditive in the base fuel is 10 to 10,000 weight parts per million,preferably from 30 to 2,000 weight parts per million, and mostpreferably from 30 to 70 parts per million of the modified succinimideper part of base fuel. If other detergents are present, a lesser amountof the modified succinimide may be used.

The modified succinimide additives of this invention may be formulatedas a fuel concentrate, using an inert stable oleophilic organic solventboiling in the range of about 150° to 400° F. Preferably, an aliphaticor an aromatic hydrocarbon solvent is used, such as benzene, toluene,xylene or higher-boiling aromatics or aromatic thinners. Aliphaticalcohols of about 3 to 8 carbon atoms, such as isopropanol,isobutylcarbinol, n-butanol and the like, in combination withhydrocarbon solvents are also suitable for use with the fuel additive.In the fuel concentrate, the amount of the additive will be ordinarilyat least 10 percent by weight and generally not exceed 70 percent byweight and preferably from 10 to 25 weight percent.

EXAMPLES Example 1

To a 500-ml reaction flask is charged 253.4 g of a succinimidedispersant composition [prepared by reacting 1 mole of polyisobutenylsuccinic anhydride--where the polyisobutenyl group has a number averagemolecular weight of 950--and 0.9 mole triethylenetraamine and thendiluting to about 50% actives with lubricating oil diluent to give amaterial with an alkalinity value (AV) of 47 mg KOH/g]. To thissuccinimide is added 26.1 g 1,3-dioxolan-2-thione. The mixture is heatedto 150±5° C. for 3 hours to yield a modified succinimide of thisinvention.

Example 2

To a 5-liter reaction flask is charged 2534 g of the succinimidedispersant composition of Example 1 and 30.6 g4-methyl-1,3-dioxolan-2-thione. The reaction mixtures is stirred andheated at 150±5° C. for 9 hours to yield a modified succinimide of thisinvention.

What is claimed is:
 1. A product produced by the process which comprisescontacting at a temperature sufficient to cause reaction a polyaminoalkenyl or alkyl succinimide and a compound of the Formula I, ##STR10##wherein R₄ is an alkalene group of from 2 to 3 carbon atoms or analkylene group of from 2 to 3 carbon atoms substituted with from 1 to 3alkyl groups of from 2 to 3 carbon atoms each.
 2. A product produced bythe process of claim 1 wherein R₄ is alkylene of from 2 to 3 carbonatoms.
 3. A product produced by the process of claim 2 wherein R₄ isethylene.
 4. A product produced by the process of claim 1 wherein thereaction is conducted at from 0° C. to 250° C.
 5. A product produced bythe process of claim 4 wherein the molar charge of the compound ofFormula I to the basic nitrogen of the polyamino moiety of thepolyaminoalkenyl or alkyl succinimide is from about 0.2:1 to about 5:1.6. A fuel composition comprising a hydrocarbon boiling in the gasolineor diesel range and from 10 to 10,000 parts per million of a compound asproduced in claim 1.